1. Technical Field
The present invention relates to a display device for a vehicle, the display device having a fuel economy display unit.
2. Related Art
A vehicle having an idling stop function has been proposed in order to improve the fuel economy performance of the vehicle, the idling stop function causing the engine to stop automatically when the vehicle is stopped. In order to prompt a driving operation which improves fuel economy, a fuel economy display unit has been proposed, such as a fuel economy meter configured to display a fuel economy difference between the current instantaneous fuel economy and the past average fuel efficiency (see Japanese Unexamined Patent Application Publication No. 2007-298494). When the idling stop is performed, both the vehicle speed and the fuel consumption are zero, and thus an instantaneous fuel economy may not be calculated and display conditions for the fuel economy meter may not be determined. Thus, an approach has been proposed in which when the idling stop is performed, the fuel economy meter is controlled at a specific predetermined display state.
Controlling the fuel economy meter at a specific predetermined display state causes the display state of the fuel economy meter to be significantly changed in a process of shifting to the idling stop, thereby causing a driver to have a feeling of discomfort. In particular, a needle-type fuel economy meter having a needle is likely to give a driver a feeling of discomfort. For example, when the vehicle is stopped, idled, and is shifted to the idling stop, the needle swings out in a direction in which fuel economy reduces in the idling which consumes fuel, and the needle returns to a specific position (for example, the middle) as the idling stop is subsequently performed. Such an excessive operation of the needle of the fuel economy meter causes a driver to have a feeling of discomfort.